628735791 has 4 divisors (see below), whose sum is σ = 838314392. Its totient is φ = 419157192.

The previous prime is 628735777. The next prime is 628735813. The reversal of 628735791 is 197537826.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 628735791 - 2¹⁹ = 628211503 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 628735791.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (628735711) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 104789296 + ... + 104789301.

It is an arithmetic number, because the mean of its divisors is an integer number (209578598).

Almost surely, 2^628735791 is an apocalyptic number.

628735791 is a deficient number, since it is larger than the sum of its proper divisors (209578601).

628735791 is a wasteful number, since it uses less digits than its factorization.

628735791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 209578600.

The product of its digits is 635040, while the sum is 48.

The square root of 628735791 is about 25074.6045033616. The cubic root of 628735791 is about 856.6880872141.

The spelling of 628735791 in words is "six hundred twenty-eight million, seven hundred thirty-five thousand, seven hundred ninety-one".